Earth moving equipment



April 7, 1942. G. l. CLARK EARTH MOVING EQUIPMENT 4 Sheets-Sheet l Filed July l, 1940 INVENTOR @era/d C/ar .IJHIMHILH ATTORNEY April 7, 1942. G. CLARK EARTH MOVING EQUIPMENT Filed July l, 1940 4 Sheets-Sheet 2 INV'ENTR Gera/0 C/ark BY Z ATTORNEY G. l. CLARK EARTH MOVING EQUIPMENT Filed July 1, 1940r 4 Sheets-Sheet 5 ,H R .v md m, mf. mw .n .fc am A 6 6 Q Y B En.

April 7,l 1942.- G. l. CLARK 2,278,829

EARTH MOVING EQUIPMENT Y Filed Ju1y`1, 1940 4 sheets-sheet 4 INVENTOR ffa/a Var/Q ATTOR N EY Patented 7, 1942 EARTH MOVING EQUIPMENT Gerald I. Clark, Sunnyvale, Calif., assignor to Wooldridge Manufacturing Company, Sunnyvale, Calif., a corporation of Nevada Application July 1, 1940, Serial No. 343,323

1 Claim.

This invention relates generally to earth moving equipment of the type utilizing an earth cutting or scraping blade, together with a bowl or like structure for receiving and carrying a load to a point of discharge. More particularly, the invention relates to earth moving equipment making use of both a main bowl structure and an auxiliary bowl cr front apron, with provision for raising the front apron and for adjusting the cutting blade during a loading operation, for closing the front apron to facilitate carrying the load, and for discharging the load from both the front apron and the main bowl structure.

An object of the invention is to provide novel and simplified equipment of the above character, particularly with respect to the mechanism for coordinating discharge of the main bowl structure with movements ofthe front apron.

A further object of the invention is to provide A Figure 1 is a side elevational view,vshowing a` machine incorporating the present invention,

with a front apron closed upon the main bowl structure; y Figure 2 is a side elevational view like Figure 1, but showing the front apron in an elevated position and with the main bcwl and its cutting blade positioned to perform digging operations;

Figure 3 is a view like Figure 1, but showing the hinged bottom for the mainv bowl structure and the front apron in their upper limiting po.- l

sitions, these being positions assumed to eiect complete discharge of a load; and

Figure 4 is a plan view of the machine as illustrated in Figure 1.

Referring first to Figures l to 3 inclusive, the machine includes a forked.frame I0, with' the two connected by the upright portions I8 and the cross beam I9. The parts of this `frame are made of beam sections of properstrength 'and may be fabricated from steel plates or structural elements welded together. The main frame I0 carries the main bowl structure 20, and this structure in turn carries the front apron or auxiliary bowl 2I.

The main bowl structure consists of the side walls 22 which arelrigidly secured to the side beams II of the frame, or incorporated with beams Il as apart of the frame. Extending across and connecting the lower edges of the side walls 22, there is a beam23 which serves as a mounting for the cutting blade 24. Disposed between the side walls 22 to the rear of beam 23, there is a load supporting bottom 25 which has its forward edge provided with a hinged connection 26 to the beam 23. As viewed in Figure l, the hinged bottom'25 has one portion 25a which extends rearwardly from the hinged connection 26, and an upwardly extending portion 25h which forms the rear wall of the main bowl structure. Side webs 21 can connect the por` tions 15a and 25h to aiord proper strength.

As viewed in Figure l, the hinged bottom 25 is in its lowermost or load carrying position, corresponding to the position which it assumes when the machine has a full load. When this member is swung upwardly and forwardly, it effects discharge of material from within the main bowl structure, with the material being delivered over the cutting blade 24. Its upper limiting position is shown in Figure 3.

The forward apronor auxiliary bowl 2l consists of side walls 28 which connect to the ends of the load supporting walls 29a,` 29h and 29C. This apron extends between the side walls 2| of the main bowl structure for the closed position shown in Figure 1. For this closed position of the front apron, its lower rear edge 3l is adjacent the cutting edge of the blade 24, wall 29a is substantially horizontal, wall portion 2gb is at an angle of about45 to the horizontal, and wall side branches or beams II extending rearwardly. The forward portion I2 of the frame has a swivel connection I3 with the frontaxle I4, which in turn carries the wheels I6. Coupling elements Il are carried by the front axle and are adapted for connection with the draft bar of a tractor. In order to strengthen the main frame I0, the rear ends of the side beams II are portion 29e is substantially vertical.

For connecting the front apron to the main bowl structure, rearwardly extending arms 32 are provided which have rigid connections to the sides of the front apron. The rear ends of these arms have alined pivotal connections 33 with the side walls 22 of the main bowl, so that the front apron may swing forwardly and upwardly to positions such as shown in Figures 2 and 3.

For the purpose of forming a novel mechanical faces 38 formed vupon the supporting arms 32 for the front apron. For the position of the parts shown in Figure 1, the cam surfaces 38 extend downwardly below the horizontal axis of the pivotal connections 33, so that as the rollers 31 track along these surfaces, the effective leverage about the axis of the pivotal connections 33 varies. Thus, when the hinged bottom 25 is swung its lowermost load carrying position, and the front apron 2| is closed or in its lowermost position. If the operator desires to take on a load, the machine is traversed over the ground, cable 5| is vslaclred olf to permit the main bowl and the cutting blade 24 to lower to digging position, and cablev 6| is pulled to partially elevate the hinged bottom 25. Figure 2 shows a typical positioning of the parts during digging or loading operations, when the machine is taking on a load. It will be noted that the front apron is in lanelevated position, and that there is ample clearance between the rear edge of this apron and the cutting edge of the main bowl structure,

for passage ofl earth. rock, boulders and the like.

' AS' the main bowl structure becomes filled with upwardly a relatively short part of its total movement, as for example to a position shown in Figure 2, the front apron 2| is swung a substantial distance upwardly and forwardly, as illustrated in this figure. Further upward swinging movement of the hinged bottom 25 causes continued upward movement of the front apron, but since the rolleration, the apron will have closed upon the cut- V er .31 is now tracking along the cam surfaces 36 4 and farther away from the axis of pivotal connections 33, the ratio between increments of movement of the hinged bottom and of the front apron continuously varies. In other words, if the hinged bottom 25 is swung at a constant speed from the position shown in Figure 1 to that shown in Figure 3 the front apron is first moved rapidly to approximately the position shown in Figure 2, and subsequently its movement is rapidly decelerated until both the hinged bottom and the front apron attain the limitingV positions shown in Figure 3. y

For the purpose of raising and lowering the cutting blade 24, a rear frame yoke v4| is provided, which has side branches or beams 42 secured to the supporting axle 43 vof the rear supporting wheels 44. The forward ends 'of the side branches 42 have pivotal connections 46 with the side branches |-I of the main frame. The rear part.of the frame 42 has upstanding portions 41 connected by the cross beam 48.

As representative of suitable power means actin g between the two frames I0 and 4|, whereby the Atwo frames can be jackknived about the pivotal connections 46, I have shown a pull cable 5| which is guided over the sheaves 52 and 53, which in turn are carried by a bracket 54 upon the cross beam 48. The cable is also reeved over a sheave 56, carried by a bracket 51 upon the cross beam I9. The end of the cable is anchored at 58, to that when cable 5| is pulled, bracket 51 is elevated with respect to bracket 54, thus ef-4 fectively raising the main bowl structure together with the cutting blade 24.

While various means can be used to apply motion to the hinged bottom 25, for operation of this part together with the front apron as previously described, it is convenient to use a pull cable 6|. This cable is guided over a sheave 62 carried by the upright 63, and is also reeved over a sheave 64 carried by the bracket 65 on cross beam 36. The end of the cable is anchored at 66. Both of the cables 5| and 6| extend forwardly to connect to suitable power driven Winches, upon the tractor. At the forward end of the machine, the

cables can engage sheave blocks 61 and 68 carried l by the supporting bracket 69. y

Operation of the machine can be reviewed as follows: Figure 1 shows the hinged bottom 25 in earth, the operator slacks off on the cable 6|, thus permitting closing movement of the front apron 2| as the nal stages of the loading operation are being completed. During the final digging stages, the earth boils forwardly to fill the front apron2l. At the end of the digging opting blade 24, and the load is supported by the hinged bottom 25 of the main bowl structure, as Well as by the front apron. The operator now pulls upon the cable 5| to a suicient degree to elevate the main bowl structure, together with the front apron, and the machine is now traversed to the point or locality where it is desired to discharge the load. A

To discharge the load, the operator pulls upon the cable 5|, thereby causing the hinged bottom to swing upwardly and forwardly to Ysimultaneously cause upward and forward movement of the front apron 2|. Thus, the lload is discharged simultaneously over the cutting blade andbetween the space between the cutting blade and thefront apron. Figure 3 represents the limiting g positions of the. hinged bottom and the front apron at the completion of the discharging operation. The parts can now be returned to norm'al position shown in Figure 1 by slacking off on cable 5|. The elements which interconnect the hinged bottom and the front apron, namely arms 34, roller 31, and the cam surfaces 38, are relatively simple parts capable of withstanding severe stresses. Also,l.these relatively simple elements provide the desired disproportionate movements to enable proper positioning of the front4 apron during loading or digging operations, without necessitating positioning of the hinged bottom 25 during such' operations in such a manner as to obstruct proper loading of the main bowl structure. Y

I claim:

In an earth mover, a main earth carrying bowl structure having an open frontl end and a forward cutting blade, said structure including side walls and a hinged bottom movable between loading and discharge positions to effect discharge of material over the cutting blade from the main bowl structure, said hinged bottom including an upwardly extending portion which forms the rear wall of the main bowl structure, wheels serving to support the main bowl structure for traversing movement, a forward apron or auxiliary bowl structure cooperating with the main bowl structure and movable between a position in which it closes the front of the main bowl and elevated positions in which earth may enter or leave the main bowl over the cutting blade, side arms attached to the forward apron and pivotally' connected to the side walls of the main bowl structure, said side arms being provided with cam surfaces located outside the main bowl but adjacent. the side walls of the bowl, rigid side arms secured to the upper edge of the upwardly extending portion of said hinged bottom, said side arms being located outside the main bowl but adjacent the side walls of the same, said side arms extending in a general horizontal dirertion for loading position of the hinged bottom, the free forward ends of said last named arms cooperating with said cam surfaces whereby movement of said bottom member from loading to discharge position causes simultaneous movement of the front apron from closed to elevated positions, and means for applying power to said hinged bottom member for movement of the same from loading to discharge positions.

GERALD I. CLARK. 

